Tunable Performance of Amorphous In-Zn-O Thin Film Transistors via Silicon Doping for Logic Circuit Integration

The effect of silicon (Si) content in the indium-zinc-oxide (IZO) system on the electrical characteristics of thin-film transistors (TFTs) has been investigated depending on various Si ratios. The SiInZnO (SIZO) TFTs exhibited excellent performance, with field-effect mobility exceeding 28cm\(^2\)V\(^{-1}\)s\(^{-1}\), a subthreshold slope of 0.506 V-decade\(^{-1}\), and an on/off current ratio over 10\(^{8}\). As Si content increased, the number of defect states decreased, resulting in enhanced threshold voltage stability and reduced subgap states, improving both mobility and bias stability. Amorphous Oxide Semiconductor(AOS) electrical properties are affected by oxygen vacancies(V\(_{o}\)) in the channel layer. These findings suggest that SIZO TFTs are promising for next-generation flexible electronics. NOT, NAND, and NOR logic circuits have been implemented simply by modulating the Si ratio on the channel layer, an excellent voltage gain was obtained using SIZO TFTs.